Raw material defects in bearings
FOSHAN CITY KURUI LIGHTING CO.,LTD , https://www.kuruilighting.com
July 26 09:28:02, 2025
[Hung Yu SKF Bearing Technology Center]
Based on the analysis of fracture toughness and other properties of SKF bearing steels, as well as the process of crack propagation in materials, it becomes clear that in high dn value applications, where hoop stress is present, the design, classification, and manufacturing methods of needle roller bearings, along with surface treatment techniques for high-speed steel and the carbon content in the hardened layer, play a critical role.
To address these challenges, SKF has developed advanced surface treatment processes aimed at increasing surface hardness and inducing beneficial compressive stresses. These treatments result in improved fatigue resistance, slower crack propagation during the second stage, and enhanced fracture toughness of the core material—especially when quenching is incomplete or carbon content is low.
The surface treatment technologies developed by SKF include:
(1) Local heat treatment using shock, electrical, or induction hardening to improve the hardness of high-speed steel that has not been fully quenched. This method helps enhance the fracture toughness of SKF bearings.
(2) Chemical heat treatment, such as carburizing or nitriding, which introduces carbon or nitrogen into the microstructure of standard high-speed steel, resulting in a hardened surface layer.
SKF believes that FAG bearings can benefit significantly from these surface treatment techniques when developing new steel grades or improving heat treatment processes for next-generation aeroengines. If the microstructure and mechanical properties of SKF bearings are fully understood through heat treatment, quenched steel and high-speed steel can be optimally utilized in aerospace bearing applications.
This information is compiled and provided by the [SKF Bearing Technology Center], and all rights of interpretation belong to the company.